/Engine/Source/Runtime/CoreUObject/Public/UObject/UObjectGlobals.h
Delegate used by SavePackage() to check whether a package should be saved
typedef TBaseDelegate_ThreeParams< bool, [UPackage](API\Runtime\CoreUObject\UObject\UPackage) *, const [FString](API\Runtime\Core\Containers\FString) &, [FOutputDevice](API\Runtime\Core\Misc\FOutputDevice) * > FIsPackageOKToSaveDelegate